Fiber rovings have been employed in a wide variety of applications. For example, such rovings have been utilized to form fiber-reinforced composite rods. The rods may be utilized as lightweight structural reinforcements. For example, power umbilicals are often used in the transmission of fluids and/or electric signals between the sea surface and equipment located on the sea bed. To help strengthen such umbilicals, attempts have been made to use pultruded carbon fiber rods as separate load carrying elements.
Another application that is particularly suited for the use of fiber rovings is in the formation of profiles. Profiles are pultruded parts with a wide variety of cross-sectional shapes, and may be employed as a structural member for window lineals, decking planks, railings, balusters, roofing tiles, siding, trim boards, pipe, fencing, posts, light posts, highway signage, roadside marker posts, etc. Hollow profiles have been formed by pulling (“pultruding”) continuous fiber rovings through a resin and then shaping the fiber-reinforced resin within a pultrusion die.
Further, fiber rovings may generally be utilized in any suitable applications to form, for example, suitable fiber reinforced plastics. As is generally known in the art, rovings utilized in these applications are typically combined with a polymer resin.
For many such applications, the fiber rovings are utilized to form fiber-reinforced tapes. The tapes may be further processed to form, for example, rods or pultruded parts as discussed above, or may themselves be utilized in a wide variety of applications. One such particularly useful application is in subsea piping, such as in the oil and gas industries, wherein the tapes are utilized to reinforce the pipe sections utilized in subsea applications.
There are many significant problems, however, with currently known rovings and the resulting applications that utilize such rovings. For example, many rovings rely upon thermoset resins (e.g., vinyl esters) to help achieve desired strength properties. Thermoset resins are difficult to use during manufacturing and do not possess good bonding characteristics for forming layers with other materials. Further, attempts have been made to utilize ravings with thermoplastic polymers in other types of applications. U.S. Patent Publication No. 2005/0186410 to Bryant, et al., for instance, describes attempts that were made to embed carbon fibers into a thermoplastic resin to form a composite core of an electrical transmission cable. Unfortunately, Bryant, et al. notes that these cores exhibited flaws and dry spots due to inadequate wetting of the fibers, which resulted in poor durability and strength. Another problem with such cores is that the thermoplastic resins could not operate at a high temperature.
Further, problems exist with presently known fiber reinforced tapes utilized in many applications, such as subsea applications. For example, tapes may be wrapped around existing products, such as pipe sections, to reinforce the pipe sections. However, presently known tapes may not adequately bond with such products to provide sufficient reinforcement.
As such, a need currently exists for an improved subsea pipe system and pipe section thereof, and for an improved method for forming a subsea pipe section. Specifically, a need currently exists for subsea piping and methods that utilizes fiber reinforced tapes for reinforcement thereof, and which tapes provide improved bonding properties. Additionally, such tapes may provide the desired strength, durability, and temperature performance demanded by subsea applications.